What is mitosis?
• The way cells divide to produce more body
cells.
Match the following:
E 1. interphase
____
B 2. prophase
____
D 3. metaphase
____
C 4. anaphase
____
A 5. telophase
____
A
B
C
D
E
1. Describe the main results of meiosis
Four haploid cells
genetically different
from each other and
from parent cell.
2. What are the principle differences between mitosis and
meiosis?
• Mitosis makes body (somatic) cells; meiosis makes gametes (sperm, egg).
• Mitosis makes 2 cells, meiosis 4.
• Daughter cells from mitosis genetically identical to parent cells; cells from
meiosis different.
• Mitosis makes diploid (2N) cells, meiosis haploid (N)
3. What do the terms diploid and haploid mean?
• Diploid = 2 sets of
chromosomes.
• Haploid = 1 set of
chromosomes.
Human body cells have 23 pairs of homologous
chromosomes, or a total of 46.
4. What is crossing over?
• Homologous
chromosomes
exchange sections
of DNA.
Chromatid
tetrad
5. In human cells, 2N = 46. How many chromosomes
would you expect to find in a sperm cell? Egg cell? White
blood cell? Explain.
• 23
• 23
• 46
Connecting Concepts. In asexual reproduction, mitosis
occurs, but not meiosis. Which type of reproduction –
sexual or asexual – results in offspring with greater genetic
variability? Explain your answer.
• Sexual, because
offspring get genes from
2 parents.
• In asexual reproduction
offspring are genetically
identical to parents.
Meiosis video
http://www.youtube.com/watch?v=D1_-mQS_FZ0